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Fabrication of the Thermoplastic Microfluidic Channels
Published on: February 3, 2008
Surface modification of polymer microfluidic devices using in-channel atom transfer radical polymerization.
Xuefei Sun1, Jikun Liu, Milton L Lee
1Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA.
Electrophoresis
|July 11, 2008
Summary
This study developed a new method for modifying microfluidic devices with a polyethylene glycol (PEG) layer using in-channel atom transfer radical polymerization (ATRP). This modification effectively prevents protein adsorption, enabling high-efficiency separations of biomolecules.
Area of Science:
- Materials Science
- Analytical Chemistry
- Biochemistry
Background:
- Microfluidic devices are crucial for various analytical applications.
- Protein adsorption on microchannel surfaces can interfere with separation processes.
- Surface modification is essential to enhance the performance and stability of microfluidic devices.
Purpose of the Study:
- To develop an in-channel surface modification technique for poly(glycidyl methacrylate)-co-(methyl methacrylate) (PGMAMMA) microfluidic devices.
- To graft a polyethylene glycol (PEG) layer onto microchannel surfaces to prevent protein adsorption.
- To evaluate the efficiency and stability of the modified microdevices for biomolecule separations.
Main Methods:
- In-channel atom transfer radical polymerization (ATRP) was employed for surface grafting.
- ATRP initiator was anchored to patterned and cover plates before thermal bonding.
- Polymerization was initiated by pumping monomer, catalyst, and ligand into the microchannels.
- X-ray photoelectron spectroscopy (XPS) was used for surface characterization.
- Electroosmotic flow (EOF) measurements were performed to assess surface modification.
Main Results:
- A stable PEG-functionalized layer was successfully grafted onto the microchannel walls.
- The modified surfaces demonstrated resistance to protein adsorption.
- The microdevices achieved fast, efficient, and reproducible separations of amino acids, peptides, and proteins.
- Separation efficiencies exceeded 1.0x10(4) plates over a 3.5 cm channel.
- In-channel modified devices exhibited superior long-term stability compared to previous ATRP techniques.
Conclusions:
- In-channel ATRP is an effective method for creating protein-resistant surfaces in PGMAMMA microfluidic devices.
- The PEG-grafted microchannels significantly improve separation performance and device longevity.
- This approach offers a promising strategy for advanced microfluidic applications in analytical and biochemical separations.
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